Webster's Revised Unabridged Dictionary · 1913

Power

Power , noun

(Zoology) Same as Poor, the fish.

Power , noun

[Old English pouer, poer, Old French poeir, pooir, French pouvoir, n. & v., from Late Latin potere, for Latin posse, potesse, to be able, to have power. See Possible, Potent, and compare Posse comitatus.]

1.
Ability to act, regarded as latent or inherent; the faculty of doing or performing something; capacity for action or performance; capability of producing an effect, whether physical or moral: potency; might; as, a man of great power; the power of capillary attraction; money gives power.
One next himself in power, and next in crime. — Milton
2.
Ability, regarded as put forth or exerted; strength, force, or energy in action; as, the power of steam in moving an engine; the power of truth, or of argument, in producing conviction; the power of enthusiasm.
The power of fancy. — Shakespeare
3.
Capacity of undergoing or suffering; fitness to be acted upon; susceptibility; -- called also passive power; as, great power of endurance.
Power, then, is active and passive; faculty is active power or capacity; capacity is passive power. — Sir W. Hamilton
4.
The exercise of a faculty; the employment of strength; the exercise of any kind of control; influence; dominion; sway; command; government.
Power is no blessing in itself but when it is employed to protect the innocent. — Swift
5.
The agent exercising an ability to act; an individual invested with authority; an institution, or government, which exercises control; as, the great powers of Europe; hence, often, a superhuman agent; a spirit; a divinity.
The powers of darkness. — Milton
And the powers of the heavens shall be shaken. — Matt. xxiv. 29
6.
A military or naval force; an army or navy; a great host. — Spenser
Never such a power... Was levied in the body of a land. — Shakespeare
7.
A large quantity; a great number; as, a power o{not transcribed} good things. [Colloquial] — Richardson
8.
(a) (Mechanics) The rate at which mechanical energy is exerted or mechanical work performed, as by an engine or other machine, or an animal, working continuously; as, an engine of twenty horse power.

The English unit of power used most commonly is the horse power. See Horse power.

(b)
A mechanical agent; that from which useful mechanical energy is derived; as, water power; steam power; hand power, etc.
(c)
Applied force; force producing motion or pressure; as, the power applied at one and of a lever to lift a weight at the other end.

This use in mechanics, of power as a synonym for force, is improper and is becoming obsolete.

(d)
A machine acted upon by an animal, and serving as a motor to drive other machinery; as, a dog power.

Power is used adjectively, denoting, driven, or adapted to be driven, by machinery, and not actuated directly by the hand or foot; as, a power lathe; a power loom; a power press.

9.
(Mathematics) The product arising from the multiplication of a number into itself; as, a square is the second power, and a cube is third power, of a number.
10.
(Metaphysics) Mental or moral ability to act; one of the faculties which are possessed by the mind or soul; as, the power of thinking, reasoning, judging, willing, fearing, hoping, etc. — I. Watts
The guiltiness of my mind, the sudden surprise of my powers, drove the grossness... into a received belief. — Shakespeare
11.
(Optics) The degree to which a lens, mirror, or any optical instrument, magnifies; in the telescope, and usually in the microscope, the number of times it multiplies, or augments, the apparent diameter of an object; sometimes, in microscopes, the number of times it multiplies the apparent surface.
12.
(Law) An authority enabling a person to dispose of an interest vested either in himself or in another person; ownership by appointment. — Wharton
13.
Hence, vested authority to act in a given case; as, the business was referred to a committee with power.

Power may be predicated of inanimate agents, like the winds and waves, electricity and magnetism, gravitation, etc., or of animal and intelligent beings; and when predicated of these beings, it may indicate physical, mental, or moral ability or capacity.

Collocations (4)
Mechanical powers , See under Mechanical.
Power loom or Power press , See Def. 8 (d), note.
Power of attorney , See under Attorney.
Power of a point (Geometry) , the result of substituting the coordinates of any point in that expression which being put equal to zero forms the equation of the curve; as, x2 + y2 - 100 is the power of the point x, y, relative to the circle x2 + y2 - 100 = 0.